This publication addresses the issue of low birthweight and what state legislatures can do to reduce its incidence, particularly in regard to ensuring prenatal care. Other than prevention of unwanted pregnancies, provison of good prenatal care is the most effective strategy for reducing the number of low birthweight babies. This text describes: (1) the causes of low birthweight in the United States; (2) reasons why legislators should be concerned about low birthweight; (3) what legislators can do to reduce its incidence; (4) federal assistance programs available to states; (5) the cost-effectiveness of prenatal care; (6) recent state activities designed to reduce low birthweight and infant mortality rates; and (7) ways states are paying for expanded prenatal care. Appendix A describes eight states' approaches to prevention of low birthweight. These approaches involve the development of successful prenatal care services; the definition of prenatal care as a right of all pregnant women; prevention of preterm labor through education; assessment of the need for prenatal care among counties and allocation of resources based on priority; a focus on high-risk pregnant women; the study of various state and city approaches to planning programs; and the use of state-specific data for presentation to legislators. Appendix B lists resources and offers a brief annotated bibliography. (BC)